My recent experience is that all computers generate a good bit of RFI. Unfortunately most new desktops come with a plastic case so a lot of RFI leaks out due to the CPU radiating. So it's best to find a system with a solid metal case which may be hard to find unless you roll your own case. However, the biggest RFI offender are external monitors. I have a late model Samsung 27 inch model that just wipes out the waterfall with noise. I also have a smaller HP model that is not nearly as dramatic but is still noisy. The quietest computer I have as far as RFI goes is a 27" iMac. It generates virtually almost no RFI. I suspect this is due to the fully enclosed aluminum case and since the display and motherboard are so close I suspect there is some additional shielding going on. I run Windows 10 either under bootcamp or Parallels and both methods work pretty well. Sometimes I prefer Parallels because I can run the SDR software and OS X at the same time. However for lots of "heavy lifting" the SDR software is going to work better under Bootcamp. The iMac can support two additional HDMI monitors, but I usually have to shut them down if I need absolutely no RFI for weak signal work. The iMac solution is definitely pricer, but it beats the aggravation of having all that RFI everywhere. I haven not tried the MacBooks which are also fully encased in aluminum.